Brain On Fire is often effective, and at times positively enraging, but one can’t help but lament the much more disquieting film that might have resulted had the filmmakers been more willing to trust the facts of Cahalan’s case to speak for themselves instead of feeling a need to shove them into uplifting platitudes

There’s undoubtedly a terrifying true story at the centre and it’s easy to see why the film’s producer Charlize Theron optioned the book but there’s something a little too flat in the delivery.

Despite Barrett's careful attention to creating an unsettling mood of existential horror by loading the soundtrack with ambient dread, and his depiction of New York as a breeding ground for overstimulated instability, Brain on Fire just sits there, inert and uninvolving.

This is a downbeat slog of a film which tells a not particularly involving story.

This embarrassingly earnest film — produced by Charlize Theron — argues for the importance of doctors going the extra mile, when textbook diagnoses won’t do.